Colorado's I-70 Hazmat Policy: The Safety Argument Has a Missing Half
Wendover Productions presents Colorado's hazardous-materials policy as a trade-off: protect motorists inside the Eisenhower Tunnel by sending fuel tankers and other dangerous cargo over Loveland Pass, a steep mountain road exposed to winter weather. The trucking industry's objection is straightforward: the state may be protecting one group of road users by exposing another to greater danger.
But the episode leaves out an important qualification: Colorado does not impose a blanket ban on hazardous-materials vehicles using the tunnel whenever Loveland Pass is open or closed.
CDOT's published rules allow certain hazardous-materials loads through the tunnel when Loveland Pass is closed, subject to authorization, controlled operating periods, a maximum speed of 30 mph and an 800-foot separation from other vehicles. Certain particularly dangerous cargoes remain prohibited regardless of pass conditions.
Justia+1
That distinction matters. The actual policy is a conditional routing and access system, not simply a choice between sending every tanker over a mountain or allowing every tanker into a tunnel.
The study did not declare the existing policy the winner
Colorado commissioned a formal risk assessment under Senate Bill 19-032. The 2020 study used two specialist modelling systems, examining fire, toxic gas and propane scenarios alongside traffic, accident data, population exposure and tunnel design. This was considerably more rigorous than simply asking whether a mountain road or a tunnel looked more dangerous.
Study (Executive Summary Only)+1
Its central finding was inconvenient for anyone seeking a simple answer:
“risk is essentially transferred between the two corridors.”
The study identified three routing arrangements worthy of further consideration:
- Retaining the existing controlled-access arrangement when Loveland Pass is closed.
- Allowing selected hazardous-materials classes through the tunnel during quiet hours, between 11 p.m. and 6 a.m.
- Allowing certain empty, still-placarded hazardous-materials vehicles through the tunnel.
It rejected unrestricted access for all hazardous-materials vehicles at all times. But it did not establish that the existing arrangement was the safest possible solution.
Study (Executive Summary Only)
There is another important qualification. The report explicitly states that its contents represent the authors' views and do not necessarily represent the official views of CDOT or the Federal Highway Administration. Its recommendations were options for decision-makers to consider, not a binding determination of public policy.
Study (Executive Summary Only)
Wendover compresses this complicated result into a reassuring institutional verdict: CDOT reviewed the policy and decided it represented the best overall balance. That is stronger than the published evidence warrants.
The numbers do not support a simple comparison
Reporting on the 2020 study disclosed some revealing figures:
- No hazardous-materials incident inside the tunnels in almost 50 years.
- 13 incidents on US 6 over Loveland Pass between 2010 and 2020.
- 25 incidents on I-70 between the western tunnel entrance and Silverthorne during the same period.
- Approximately 2,429 hazardous-materials vehicles escorted through the tunnels annually when Loveland Pass was closed.
- More than eight hazardous-materials vehicles per hour travelling over Loveland Pass in both directions.
HazmatNation
These figures cannot establish which route is safer without accounting for vehicle exposure, cargo types, distance travelled and incident severity. Zero tunnel incidents under restricted access does not prove that unrestricted tunnel access would be safe. Equally, incidents on Loveland Pass demonstrate that keeping tankers out of the tunnel does not eliminate the underlying danger.
The video provides none of this numerical context.
The strongest evidence actually supports caution
There is a legitimate case for CDOT's position. An earlier 2006 CDOT-commissioned risk assessment estimated 13.90 expected annual casualties under unrestricted hazardous-materials access through I-70 and the tunnel, compared with 7.28 under the existing US 6 routing arrangement. Tunnel fire scenarios accounted for much of the difference.
EJMTPhaseIIReport.doc+1
But those estimates came from an older model using early-2000s accident data. The study also excluded the convoy effect and the interaction between passenger cars and hazardous-materials trucks. Its unrestricted-access scenario was not equivalent to the controlled arrangements subsequently evaluated.
EJMTPhaseIIReport.doc+1
Importantly, the same report recommended improvements to Loveland Pass, including a hazardous-materials-capable runaway truck ramp near milepost 220, better accommodation for nighttime recreational traffic, and measures to reduce dangerous cargo movement inside tankers.
The researchers did not regard the mountain route as harmless. They recommended retaining the routing policy while improving the road carrying the risk.
That distinction matters. A policy can be justified without its alternative being safe.
The ski-commuter argument misses the economic stakes
The trucking industry's description of the policy as sacrificing driver safety for ski commuters is an interested party's framing, not a complete account of the transportation system.
CDOT's 2024 Colorado Freight Plan describes the Eisenhower Tunnel as an important connection for moving goods between Colorado's eastern and western slopes. It also identifies I-70 as a major east-west freight corridor serving interests beyond local tourism.
freight.colorado.gov+1
The 2020 assessment considered four distinct areas of risk:
- Human casualties.
- Public infrastructure damage.
- Environmental consequences.
- Regional economic losses.
A hazardous-materials incident on Loveland Pass could threaten the Snake River and Dillon Reservoir. An incident along I-70 could threaten Clear Creek and Straight Creek. A serious tunnel incident could disrupt freight and travel between Denver and western Colorado.
Neither route offers a consequence-free solution.
The video should have challenged the industry's framing rather than allowing the argument to rest on a contest between truck drivers and ski traffic.
The investigation continued after the video
There is a particularly important development that changes the picture.
CDOT's 2024 Colorado Freight Plan records that the department began another quantitative risk investigation in 2022, involving additional work on three specific issues:
- Whether empty hazardous-materials vehicles could safely use the tunnel.
- Whether additional foam concentrate could improve the existing fire-suppression system.
- How electric-vehicle fires differ from tanker fires.
The investigation combined DG-QRAM and TuRisMo risk-modelling systems to compare the two routes and evaluate tunnel-specific safety improvements. Its first-phase findings suggested that overall risk could be reduced through targeted mitigation measures, although the assessment was still ongoing in the 2024 account.
freight.colorado.gov
A December 2024 paper by members of the risk-assessment team, Bernhard Kohl, Arnold Dix and Oliver Heger, likewise described the investigation as ongoing and identified measures with promising risk-reduction potential.
davidpublisher.com
This is not a final endorsement of sending tankers through the tunnel. It is evidence that the engineering question remained open and that improvements to the existing arrangement were still being investigated.
The public federal repository also provides only the seven-page executive summary of the 2020 study, with the full report listed as available by request. That limits independent examination of its detailed modelling results.
Study (Executive Summary Only)+1
A real-world test came in 2025
On June 15, 2025, a landslide buried Loveland Pass beneath mud and silt. The debris was approximately 100 feet wide and 15–20 feet deep, with the material released after snowmelt saturated the slope above the road.
CDOT closed the pass and escorted hazardous-materials trucks through the Eisenhower-Johnson tunnels at the top of each hour, temporarily stopping ordinary traffic.
Colorado Department of Transportation
This demonstrated something important: the tunnel exception is an operational part of the safety system, not merely a theoretical alternative. The policy must respond to changing road conditions, including landslides, not just snow and avalanches.
Colorado's current regulations also distinguish between hazardous-materials classes. Some are prohibited from the tunnels at all times; others may pass only when Loveland Pass is closed, with authorization, staging and strict operating restrictions.
sos.state.co.us
A single blanket description of hazardous-materials traffic cannot adequately explain that system.
The verdict: A complicated safety decision presented as a settled answer
I am not arguing that CDOT should allow gasoline tankers through the Eisenhower Tunnel. The potential consequences of a major tunnel fire are real, and the earlier quantitative assessment provides a serious reason for caution.
The failure is how Wendover handles the evidence.
The episode introduces a legitimate concern from trucking advocates, invokes a feasibility study, and leaves viewers with the impression that CDOT has established the existing arrangement as the best overall safety solution.
But the 2020 study identified risk transfers and several alternatives worth further consideration. A second investigation began in 2022, and subsequent research continued exploring ways to reduce risk across both corridors.
The episode never gives viewers the comparative evidence necessary to judge whether the risks are fairly distributed, whether the existing arrangements are optimal, or whether targeted improvements could produce a safer outcome.
A government retaining a policy is not proof that the policy is optimal. A dangerous alternative is not proof that the existing arrangement is fair.
Wendover explains how engineers build roads with extraordinary detail. But when it reaches the question of who should bear the danger of using one, it substitutes a neat institutional answer for an unfinished engineering and public-safety problem.
That is the weakness worth investigating.
References
1. How to Build a Road — Wendover Productions, August 11, 2023. Original video. The original account and the statements under examination.
2. Transportation of Hazardous Materials Through Eisenhower-Edwin C. Johnson Memorial Tunnel — Study — CDOT / Stantec, December 2020. Executive summary (PDF). Establishes the risk-transfer finding, modelling methods and alternative routing options; the publicly available copy is only the executive summary.
3. Rules Governing the Use of Tunnels on Colorado State Highways, 2 CCR 601-8 — Colorado Secretary of State. Current published regulations (PDF). Establishes which hazardous-materials categories can use the tunnel and under what restrictions.
4. Risk Analysis Study of Hazardous Materials Trucks through Eisenhower/Johnson Memorial Tunnels — Parsons Brinckerhoff Quade & Douglas, CDOT, June 2006. Full report (PDF). Provides the earlier quantitative comparison and its recommendations for improving Loveland Pass.
5. CDOT Releases Study Assessing Risks of Hazmat Vehicles in Eisenhower Tunnel — HazmatNation, February 8, 2021, originally published by Summit Daily. Article. Reports the historical incident counts, tunnel exposure figures and stakeholder concerns.
6. Colorado Freight Plan — Technical Analysis — Colorado Department of Transportation, April 2024. Full report (PDF). Documents the later quantitative investigation, its additional research questions and its preliminary risk-reduction findings.
7. Is International Experience of Risk-Based Decision Making for Road Tunnel Safety Applicable in the Unique US-American Regulatory Environment? — Bernhard Kohl, Arnold Dix and Oliver Heger, Journal of Civil Engineering and Architecture, Volume 18, 2024, pages 581–590. Research paper. Explains the combined risk-modelling approach and confirms that the follow-up assessment remained ongoing.
8. Stage One of Loveland Pass Clean-up Operation Nearly Complete — Colorado Department of Transportation, June 17, 2025. Official announcement. Documents the landslide, road closure and actual escorted hazardous-materials passage through the tunnels.